Surgical fastener with predetermined resorption rate

Abstract

A resorbable screw fastener and a method of firing with an applicator capable of applying a surgical fastener to tissue in order to form tissue connection to secure objects to tissue, the fastener including a body portion having a helical thread, a head portion disposed at the proximal end of the body portion. The resorbable screw fastener is 100% resorbed in vivo during a period of time ranging from about 14 days to about one year after implantation.

1. A resorbable screw fastener comprising:
 a body portion defining a longitudinal axis and having a proximal end and a distal end, the body portion having a helical thread formed thereon; and 
 a head portion disposed at the proximal end of the body portion, the head portion having a driver receiving structure defining a slot formed in an outer radial side surface of the head portion, the driver receiving structure being configured for receiving both a linear and a rotational force, the head portion including a substantially flattened surface formed in an outermost diameter thereof, wherein the substantially flattened surface of the head portion is in radial registration with a substantially flattened surface formed in an outermost diameter of the helical thread, wherein the substantially flattened surface formed in the outermost diameter of the helical thread projects partially radially inward from the outermost diameter of the helical thread and does not project into the body portion, 
 wherein absorption of the resorbable screw fastener is nearly complete at approximately 12 months post implantation. 
 
     
     
       2. The resorbable screw fastener of  claim 1 , wherein the resorbable screw fastener is formed of at least one material selected from the group consisting of trimethylene carbonate, caprolactone, dioxanone, glycolic acid, lactic acid, glycolide, lactide, homopolymers thereof, copolymers thereof, and combinations thereof. 
     
     
       3. The resorbable screw fastener of  claim 1 , wherein the resorbable screw fastener is formed of a glycolide-lactide copolymer. 
     
     
       4. The resorbable screw fastener of  claim 3 , wherein the glycolide-lactide copolymer possesses glycolide in an amount ranging from about 10% to about 50% of the glycolide-lactide copolymer and lactide in an amount ranging from about 90% to about 50% of the glycolide-lactide copolymer. 
     
     
       5. The resorbable screw fastener of  claim 3 , wherein the glycolide-lactide copolymer possesses glycolide in an amount ranging from about 15% to about 45% of the glycolide-lactide copolymer and lactide in an amount ranging from about 85% to about 55% of the glycolide-lactide copolymer. 
     
     
       6. The resorbable screw fastener of  claim 1 , wherein the resorbable screw fastener is formed of a glycolide-trimethylene carbonate copolymer. 
     
     
       7. The resorbable screw fastener of  claim 6 , wherein the glycolide-trimethylene carbonate copolymer possesses glycolide in an amount ranging from about 50% to about 90% of the glycolide-trimethylene carbonate copolymer and trimethylene carbonate in an amount ranging from about 10% to about 50% of the glycolide-trimethylene carbonate copolymer. 
     
     
       8. The resorbable screw fastener of  claim 6 , wherein the glycolide-trimethylene carbonate copolymer possesses glycolide in an amount ranging from about 55% to about 70% of the glycolide-trimethylene carbonate copolymer and trimethylene carbonate in an amount ranging from about 30% to about 45% of the glycolide-trimethylene carbonate copolymer. 
     
     
       9. The resorbable screw fastener of  claim 1 , wherein the resorbable screw fastener maintains 80% of its original strength for a period of time ranging from about 5 days to about 45 days after implantation. 
     
     
       10. The resorbable screw fastener of  claim 1 , wherein the resorbable screw fastener maintains 80% of its original strength for a period of time ranging from about 7 days to about 30 days after implantation. 
     
     
       11. The resorbable screw fastener of  claim 1 , wherein the resorbable screw fastener wherein the resorbable screw fastener is 100% resorbed in vivo during a period of time ranging from about 21 days to about 3 months after implantation. 
     
     
       12. The resorbable screw fastener of  claim 1 , wherein the resorbable screw fastener wherein the resorbable screw fastener is 100% resorbed in vivo during a period of time ranging from about 28 days to about 2 months after implantation. 
     
     
       13. The resorbable screw fastener of  claim 1 , wherein said body portion includes a center shaft that is tapered from a narrow distal end to a larger proximal. 
     
     
       14. The resorbable screw fastener of  claim 1 , wherein said distal end of the body portion is blunt. 
     
     
       15. The resorbable screw fastener of  claim 1 , wherein the land of the thread is substantially perpendicular to the longitudinal axis. 
     
     
       16. The resorbable screw fastener of  claim 1 , wherein a distance of the thread is substantially enlarged. 
     
     
       17. The resorbable screw fastener of  claim 1 , wherein the distance of the head portion is about 3.8 mm. 
     
     
       18. The resorbable screw fastener of  claim 1 , wherein a height of the head portion is about 1.5 mm. 
     
     
       19. The resorbable screw fastener of  claim 1 , wherein a length of the body portion is about 5 mm in length. 
     
     
       20. The resorbable screw fastener of  claim 1 , further including a lumen extending through an entire length thereof. 
     
     
       21. The resorbable screw fastener of  claim 20 , wherein said body portion has a circular cross section. 
     
     
       22. A method of inserting a resorbable screw fastener of  claim 1 , the method comprising the steps of tapping the target tissue with a pilot, and installing the resorbable screw fastener by applying linear and rotational force on the head portion. 
     
     
       23. A resorbable screw fastener and instrument for inserting the resorbable screw fastener, comprising:
 an instrument having an outer tube on a distal end and a trigger mechanism on its proximal end; and 
 a resorbable screw fastener having a body portion and a head portion disposed at the proximal end of the body portion, the body portion having a helical thread formed thereon, the fastener being inserted on the distal end of the instrument, the head of the resorbable screw fastener having a driver receiving configuration defining a slot formed in an outer radial side surface for transmitting both linear and rotational motion to the body portion, the head portion including a substantially flattened surface defined in an outermost diameter thereof, wherein the substantially flattened surface of the head portion is in radial registration with a substantially flattened surface formed in an outermost diameter of the helical thread without projecting into the body portion, 
 wherein absorption of the resorbable screw fastener is nearly complete at approximately 12 months post implantation. 
 
     
     
       24. A resorbable screw fastener comprising:
 a body portion defining a longitudinal axis and having a proximal end and a distal end, the body portion having a helical thread formed thereon, the helical thread having a first distance and the body portion having a second distance; and 
 a head portion disposed at the proximal end of the body portion, the head portion having a driver receiving structure defining a slot formed in an outer radial side surface for transmitting rotational motion to the body portion, the head portion having an outer diameter substantially equal to the first distance of the helical thread, the head portion including a substantially flattened surface defined in an outermost diameter thereof, wherein the substantially flattened surface of the head portion is in radial registration with a substantially flattened surface formed in an outermost diameter of the helical thread, 
 wherein the substantially flattened surfaces of the head portion and the helical thread are disposed between the second distance of the body portion and the first distance of the helical thread without projecting into the body portion, and 
 wherein absorption of the resorbable screw fastener is nearly complete at approximately 12 months post implantation. 
 
     
     
       25. The resorbable screw fastener of  claim 24 , wherein the resorbable screw fastener is formed of at least one material selected from the group consisting of trimethylene carbonate, caprolactone, dioxanone, glycolic acid, lactic acid, glycolide, lactide, homopolymers thereof, copolymers thereof, and combinations thereof. 
     
     
       26. The resorbable screw fastener of  claim 24 , wherein the resorbable screw fastener is formed of a glycolide-lactide copolymer. 
     
     
       27. The resorbable screw fastener of  claim 26 , wherein the glycolide-lactide copolymer possesses glycolide in an amount ranging from about 10% to about 50% of the glycolide-lactide copolymer and lactide in an amount ranging from about 90% to about 50% of the glycolide-lactide copolymer. 
     
     
       28. The resorbable screw fastener of  claim 26 , wherein the glycolide-lactide copolymer possesses glycolide in an amount ranging from about 15% to about 45% of the glycolide-lactide copolymer and lactide in an amount ranging from about 85% to about 55% of the glycolide-lactide copolymer. 
     
     
       29. The resorbable screw fastener of  claim 24 , wherein the resorbable screw fastener is formed of a glycolide-trimethylene carbonate copolymer. 
     
     
       30. The resorbable screw fastener of  claim 29 , wherein the glycolide-trimethylene carbonate copolymer possesses glycolide in an amount ranging from about 50% to about 90% of the glycolide-trimethylene carbonate copolymer and trimethylene carbonate in an amount ranging from about 10% to about 50% of the glycolide-trimethylene carbonate copolymer. 
     
     
       31. The resorbable screw fastener of  claim 29 , wherein the glycolide-trimethylene carbonate copolymer possesses glycolide in an amount ranging from about 55% to about 70% of the glycolide-trimethylene carbonate copolymer and trimethylene carbonate in an amount ranging from about 30% to about 45% of the glycolide-trimethylene carbonate copolymer. 
     
     
       32. The resorbable screw fastener of  claim 24 , wherein the resorbable screw fastener maintains 80% of its original strength for a period of time ranging from about 5 days to about 45 days after implantation. 
     
     
       33. The resorbable screw fastener of  claim 24 , wherein the resorbable screw fastener maintains 80% of its original strength for a period of time ranging from about 7 days to about 30 days after implantation. 
     
     
       34. The resorbable screw fastener of  claim 24 , wherein the resorbable screw fastener wherein the resorbable screw fastener is 100% resorbed in vivo during a period of time ranging from about 21 days to about 3 months after implantation. 
     
     
       35. The resorbable screw fastener of  claim 24 , wherein the resorbable screw fastener wherein the resorbable screw fastener is 100% resorbed in vivo during a period of time ranging from about 28 days to about 2 months after implantation. 
     
     
       36. The resorbable screw fastener of  claim 24 , wherein the slot extends the entire length of the screw fastener. 
     
     
       37. The resorbable screw fastener of  claim 24 , wherein the distal end of the body portion defines a distal surface which is angled with respect to the longitudinal axis. 
     
     
       38. The resorbable screw fastener of  claim 37 , wherein the distal surface of the distal end of the body portion is angled at about 5° to about 15° with respect to an axis which is perpendicular to the longitudinal axis. 
     
     
       39. The resorbable screw fastener of  claim 24 , wherein the head portion defines a distal surface which is angled with respect to the longitudinal axis. 
     
     
       40. The resorbable screw fastener of  claim 39 , wherein the distal surface of the head portion is angled at about 5° to about 15° with respect to an axis which is perpendicular to the longitudinal axis. 
     
     
       41. The resorbable screw fastener of  claim 40 , wherein the distal surface of the distal end of the body portion is angled at about 5° to about 15° with respect to an axis which is perpendicular to the longitudinal axis. 
     
     
       42. The resorbable screw fastener of  claim 41 , wherein each slot formed in each thread includes at least one of a radiused leading edge and a radiused trailing edge. 
     
     
       43. A resorbable screw fastener comprising:
 a body portion defining a longitudinal axis and having a proximal end and a distal end, the body portion having a helical thread formed thereon, the helical thread having a first distance and the body portion having a second distance; and 
 a head portion disposed at the proximal end of the body portion, the head portion having driver receiving structure defining a slot formed in an outer radial side surface for transmitting both linear and rotational motion to the body portion, the head portion having an outer diameter substantially equal to the first distance of the helical thread, the head portion including a substantially flattened surface defined in an outermost diameter thereof, wherein the substantially flattened surface of the head portion is in radial registration with a substantially flattened surface formed in an outermost diameter of the helical thread, 
 wherein the substantially flattened surfaces of the head portion and the helical thread are disposed between the second distance of the body portion and the first distance of the helical thread without projecting into the body portion, 
 wherein the resorbable screw fastener has a shear strength of about 3.5 pounds to about 5.5 pounds during a period of time ranging from the time of implantation in vivo to about one week after implantation, a shear strength ranging from about 0.5 pounds to about 4.2 pounds during a period of time ranging from about one week to about 1.5 weeks after implantation, and a shear strength of about 0 pounds about one year after implantation. 
 
     
     
       44. The resorbable screw fastener of  claim 1 , wherein the resorbable screw fastener is heated to from about 100° C. to about 160° C. for a time of from about 2 hours to about 24 hours.